[css] enable strict on server

extensions/css-language-features/server/src/utils/runner.ts

@@ -0,0 +1,47 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+'use strict';
+
+import { ResponseError, ErrorCodes, CancellationToken } from 'vscode-languageserver';
+
+export function formatError(message: string, err: any): string {
+	if (err instanceof Error) {
+		let error = <Error>err;
+		return `${message}: ${error.message}\n${error.stack}`;
+	} else if (typeof err === 'string') {
+		return `${message}: ${err}`;
+	} else if (err) {
+		return `${message}: ${err.toString()}`;
+	}
+	return message;
+}
+
+export function runSafe<T, E>(func: () => T, errorVal: T, errorMessage: string, token: CancellationToken): Thenable<T | ResponseError<E>> {
+	return new Promise<T | ResponseError<E>>((resolve, reject) => {
+		setImmediate(() => {
+			if (token.isCancellationRequested) {
+				resolve(cancelValue());
+			} else {
+				try {
+					let result = func();
+					if (token.isCancellationRequested) {
+						resolve(cancelValue());
+						return;
+					} else {
+						resolve(result);
+					}
+
+				} catch (e) {
+					console.error(formatError(errorMessage, e));
+					resolve(errorVal);
+				}
+			}
+		});
+	});
+}
+
+function cancelValue<E>() {
+	return new ResponseError<E>(ErrorCodes.RequestCancelled, 'Request cancelled');
+}